Federal Intervention: A Congressional investigation of Southern violence prompts President Grant to crack down on the Ku Klux Klan.

V/O Court Officer
"State your age, where you were born, and where you now live."

V/O Abram Colby's Testimony
"I am fifty two years old. I was born in Greene County and it is my home now... when I can live there."

NARRATOR
In October 1871, two years after the attack that nearly cost him his life, Abram Colby testified before a Congressional committee. His back had been badly injured, and he had lost the use of his left hand. But he'd gone back to the Georgia legislature. And he continued to campaign against Klan violence.

V/O Abram Colby's Testimony
"No man can make a free speech in my county. I do not believe it can be done anywhere in Georgia... If you go there you will be killed, or shot at, or whipped, or run off."

NARRATOR
The growing number of attacks like the one on Colby had finally prompted a federal investigation. Hundreds of witnesses risked their lives to tell their stories. Northerners who cared little about the fate of blacks in the South were horrified by the accounts in the newspapers.

FONER
It really reveals to the country the extent of these kinds of atrocities and terrorism in the South.

AYERS
Grant realizes "We've got to stop this. We can't just allow everything that we're trying to accomplish to be destroyed by the flagrant acts of these white vigilantes in the South."

NARRATOR
Grant understood that the memories of war, North and South, were still raw, and felt he couldn't risk full-scale intervention. He could, however, set an example in one state, South Carolina, where Klan terror was at its bloodiest. In the fall of 1871, he declared martial law. Scores of suspected Klan leaders were rounded up and tried in federal courts.

AYERS
It's infuriating to white southerners that they would come in, impose this national power in their own homes, doubt their word, solicit the testimony of former slaves. This is something that would just insult white southerners more than anything that had been done up to this point.

NARRATOR
By the end of the trials, federal prosecutors had destroyed the Klan in South Carolina. Grant's crackdown had brought a measure of peace -- for the time being.